Hardware RAID vs OS RAID
Posted on 2016-09-30
Still trying to make an informed decision. Rindi I am really not trying to pick on you or make your life miserable. I am trying to make an informed decision and your knowledge of OS RAID is unmatched and your input greatly appreciated. I set up a Server 2012 with two Intel 540s SSD drives (480MB on the motherboard SATA ports using AHCI. I then mirrored the volumes.
On the good side TRIM was still supported on this RAID 1 configuration. TRIM was not supported on the Adaptec 8405 in a RAID 5 configuration (same SSD drives)
Now the downside (benchmarking with HDTune Pro):
Motherboatd SATA Port. Single SSD. Not yet mirrored:
Min Transfer : 218MB/s
Max Transfer: 225MB/s
Average Transfer: 222MB/s
Motherboatd SATA Port. Single SSD. Mirrored:
Min Transfer : 192MB/s
Max Transfer: 224MB/s
Average Transfer: 204MB/s
Adaptec 8405 RAID 5 (Same SSD Drives):
Min Transfer : 547MB/s
Max Transfer: 643MB/s
Average Transfer: 587/s
It appears as though the throughput is about two to three times better with a hardware RAID controller. The downside is that the RAID controller with battery backup and a third drive for RAID 5 is another $600 (but the usable space does increase 480GB in RAID 5). Do those transfer numbers seem real to you? Thoughts?
Lastly LOL! I pulled drive 0 to see what would happen. No visible or audible notification. Can you set notification via email?
Now disk manager shows Drive an unknow drive as "missing". I plugged the drive back in thinking it would automatically remirror and it didn't. Drive 0 now shows up as Foreign. How do I re-establish the mirror?
I am going to keep playing with OS RAID. I want to give it a fair shot.